I'd be willing to defend Apple's 30% cut if any of it was justified. Instead, my experience working in the walled garden has been gruelling. Xcode is a pathetic disaster at this point, but Apple seems to be unwilling to extend any functionality to the editors I actually use. Getting an app through the guidelines is an exercise in arbitrary debasement. Their phone support is useless too, with most of them directing me to forum posts that basically say "don't do whatever you're doing". I think Epic has every right to offer their lower commission, because their service downright sucks. I still plan to buy games from Steam for the foreseeable future, because their work on Proton is worth it to me.

I am pretty sure it is established that there was, Amazon and Apple were the first 2 members

Apple and Amazon are far from the first storefronts.

Steam was charging 30% as far back as 2003.